Inside the still highly radioactive Fukushima plant

Fukushima Daiichi nuclear plant operator Tokyo Electric Power Company (Tepco) released video footage on Wednesday showing the interior of No. 2 reactor building where radiation levels still too high for human workers.

The video of the fifth floor of the No. 2 reactor building was taken by Quince 2, a domestically developed robot designed to be sent into areas such as the Fukushima nuclear plant.

Human workers have yet to enter the fifth floor of the No. 2 reactor and while part of the No. 2 reactor building was filmed by the first Quince robot last year, it's signal was lost and was subsequently unable to be retrieved.

Driving around the fifth floor of the building, the Quince 2 robot measured radiation readings of up to 220 millisieverts an hour even though nearly a year has passed since the nuclear disaster occurred.

Most people are exposed to natural radiation of 2-3 millisieverts per year.